1. How do I know if my computer and sound card are compatible with the RoMac 10  Band Equalizer 2012?

If you hear a trailing echo while listening to yourself through your computer speakers or through the monitor on your radio, you are probably hearing audio from the speaker going back into the microphone. Many times an operator will then turn up the volume on the speaker to listen to the echo closer, and will exacerbate the problem. When the software is hooked up to your radio, this will not be an issue.

This point can not be stressed enough. When listening through a set of speakers, or even using a boom headset, the microphone may pick up the audio and sound like an echo.

Best to use headphones, or keep the speaker volume turned down as low as possible, while testing.

When installing a PCI sound card use a slot that is as far away from other cards installed in the computer, especially video cards. This will help in reducing any noise picked up from other cards installed in your computer.

If you hear low level unprocessed audio followed very shortly by processed audio, check the following:
1) Windows 7 only - Check to see if "Listen to This Device" is checked in the Windows Record Mixer, under "Listen" tab.
2)  If the "No Mon" on the sound card level dialog is available, make sure that it is checked.
3)  The mute checkbox on the Microphone on the Play Side is checked.
4)  If neither control is available (grayed out)  you may have to use the software that came with your sound card. Some sound cards have very proprietary controls. Look for something along the lines of  a "Monitor" function. This need to be disabled and/or muted.

See Help File under "Sound Card Trouble Shooting" for help in solving interruptions in the audio stream.

Some sound cards need a microphone plugged into the Mic jack and/or something in the Line In jack in order for Windows to recognize the input devices. If you get an error message about no sound card "capture device" found your sound card may require something to be plugged in.

2. I get reports of distorted audio while using the RoMac 10 Band Equalizer.
   

The peak indicator of the equalizer should be peaking up about 1/3 to 1/2 the way up. None of the indicators should ever be yellow or red. See the help file for the equalizer to understand setting up the audio levels in your system.

If adjusting the audio levels doesn't help, it is probably RF getting into the system. A quick way to confirm this, is to reduce your power to an absolute minimum. If the distortion is gone, or much reduced, then you have RF getting into the system.

A trailing echo that is very distorted and much reduced in volume, is an indication that RF is getting into audio system. Some sound cards may manifest RF problems by the audio stream being interrupted, much like if the computer is to busy and the buffers in the software aren't set large enough.

West Mountain products (other manufacturers may do the same) have a jumper position in their microphone jumper scheme,  called "GNDTIE"  Ensure a jumper is NOT placed across the "GNDTIE" position. If the jumper is installed, this will setup a ground loop in the PTT circuit.

Some West Mountain (other manufacturers may do the same) supplied cables to connect their interface units and the radio's microphone input have a bare piece of wire on the microphone minus pin that gets pressed against the 8 pin connector case. If your connector has this wire, remove it. This practice will setup a ground loop problem between the microphone minus and the radios ground. 

The use of an isolation transformer is a necessity. The reason you need an isolation transformer is to ensure the sleeve connection from the sound card output is not grounded. Click here for sample interface circuits. Photograph of simple interface here. Another inexpensive solution is a "Direct Box" that is used in the Music Industry

The sleeve is on a sound card line out is not ground. It's common to the two stereo channels. If you try connecting the sound card to the transceiver without an isolation transformer, the sleeve will be grounded at the radio.

If you have built your own interface, enclose it in a metal box, not plastic. Make sure that neither side of the input (from sound card line out) to the isolation transformer is grounded. A convenient way to address this issue, is to bring the cable directly inside the metal case (with a grommet) , with an appropriate plug on the other end.

Keep the cables going to and from the computer's sound card as short as practicable. The longer the cables are, the more they will look like "antennas" and will pick up RF quite readily.

Use quality shielded cable and shielded type connecters. Make sure all connections are tight and soldered well.

Make sure the computer case is well grounded to the stations ground. Do not use a small gauge wire, use a piece of coax braid, preferably 1/2" wide. Make it as short as practicable.

When trouble shooting, disconnect as many cables as you can. This will help in locating the problem. Sometimes disconnecting a ground, on a piece of equipment in your shack, may actually help.

You may need to place ferrite cores (Common Mode Chokes) at the Line Out, Line In , and Microphone In, at the computer end and/or on the sound card interface end.

If you are using a USB sound card, you may need chokes at one or both ends of the USB cable.

If you hear yourself all garbled in the computer speakers, while transmitting, and you are using a sound card interface, you may need to place ferrite chokes on the audio in, power cord, and the audio jumper between the speakers, all at the powered speaker end.

For larger cables, or stubborn RF, use 8 to 10 turns on a 2.4 inch type 43 or type 31 material core.  For smaller cables use 2 to 3 turns type 31 material.

Do not use unknown ferrite material. Using unknown ferrite material just won't work properly! This point can not be stressed enough. Pass up the Hamfest torrids and purchase the proper material.

Type 31 snap on beads is available from Mouser part number 623-0431167281.  Type 43 material, 2.4 inch core, Amidon part number FT-240-43. Type 31, 2.4 inch core, Amidon  part number FB-31-24001

Photographs of typical chokes here...

Do not tie your microphone ground and the PTT ground together on your radio's microphone connector. Keep them separate. Make sure the PTT ground is ground. Some ready made cables on the market do this. There is also a misconception that you should run a piece of bare wire from your microphone ground pin, to the body of a 8 pin microphone connector. This is just asking for trouble!

For really stubborn cases of RF on the audio, you may want to remove the sound card and bypass the tip and sleeve of the Mic In, Line In, and Line Out with .01 uF capacitors. Even though today's sound cards built using surface mount components, the area around the audio jacks still should have some room to work. You will need to an ohm meter to find which connections are the ground, ring and tip.
Note: This is only a cure for RF problems that are propagated via differential mode. Which is rare if you have used isolation transformers.

Read this excellent article on RFI problems and how to solve them (pdf format)

3. I sometimes get reports that it seems that my last syllable of a word is being clipped.

If you are keying your transmitter with a manual PTT arrangement, make sure to leave your PTT switch down just a bit longer than normal. If you are using the audio stream from the equalizer to drive the VOX in your transmitter, this will not be an issue.

There is a "PTT delay" adjustment to delay dropping the PTT signal when using a sound card interface. Under "Settings Menu->Misc".

4. RigBlaster Pro Setup

5. Other stations seem hear a "leading echo" at a much reduced level. Especially prevalent when using the noise gate.

6. When using the software there is a "burst" of noise when the software is placed into the transmit mode when in the "Rig Interface" mode or the Space Bar" mode.
   
   

7. Typical  microphones and sound cards.

8. There seems to be a "Trailing Echo" that is much reduced in volume  
   
   

9. Even when I set the buffers to "Large" and the sampling rate down to 22050, I still get interruptions in the audio stream when I access other software.

10. Turtle Beach Sound Card under Windows Vista or Windows 7 (32 bit only)

11. My sound card doesn't have separate Microphone Inputs and Line In inputs.
    

12. My computer doesn't have a serial port.